From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B45FBC982FA for ; Tue, 22 Sep 2026 14:46:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9210D6B0095; Tue, 22 Sep 2026 10:46:09 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8F9A76B009B; Tue, 22 Sep 2026 10:46:09 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 80F976B009D; Tue, 22 Sep 2026 10:46:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 4B3A16B0095 for ; Tue, 22 Sep 2026 10:46:09 -0400 (EDT) Received: from smtpin13.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay03.hostedemail.com (Postfix) with ESMTP id D2A33A0521 for ; Tue, 22 Sep 2026 14:46:08 +0000 (UTC) X-FDA: 85241673216.13.C978831 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf01.hostedemail.com (Postfix) with ESMTP id 1036340016 for ; Tue, 22 Sep 2026 14:46:06 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=R4cgEaXF; spf=pass (imf01.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1790088367; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=s/VLxv9NKbJXTt3b3nNSK4io2b3mM5NUoxiDUVgGmts=; b=fhB/w8T/s3eB3C8fabFw1h6zbrWs/INgwqOR3/geb5Ni/E3yU87yRllshvyubPzlpxpKWj jIcQDIJS5LZqmXyLbmI/2ziMh1k/t/XT2NhaKLC5QNIfLpnDk0or0frHqNNJHzivCF36c9 NO1vYTyu7OOKULD8BIwxdxtyYSPSRcY= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790088367; b=A7aVhonIS24yUWerE8dGNCCLwPeSgE2KsKncvHDZ8gJqdT3gTDD5JVaPwAwOhN0FEUFdyx px77RBsV7xCOXIPPlB7CmJ3cMEIE9yRiFxqvHFIsV8pdDddE5lFcwYgRHd0T54i6Dn34cH a3B+rgYwUTtdj6UN3v1lnG+tliIClLA= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=R4cgEaXF; spf=pass (imf01.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 43CF16020F; Tue, 22 Sep 2026 14:46:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F87F1F000FF; Tue, 22 Sep 2026 14:45:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790088366; bh=s/VLxv9NKbJXTt3b3nNSK4io2b3mM5NUoxiDUVgGmts=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=R4cgEaXFbD6AS4kaCKua7Vb3e7Vza69BPqCaKFneNWSJQ+ddLeyxTDXFiVRcb4t6Z CN6YHPE6pQ6CRwNgjNVz02pOs4ie6lCoOSfSTFnCPfOGDjtMZS0I5TdmFw1MfBYoVU T+tYkWMTQsWIbQyxL5qMsti+vHneTm2Ym1e0aTgNENwoMXBLWkVjqoSIjJcubodobW PEPxANCUHf+m7MPFg6/8jLVqz/JMeR3FWoQDNOxwm1Pm8k1Fd0BNTEcmpx41+ZvO9W DUhHRMShYQKEeA5BQSiPEDB90RPaiRRqGKtweokjXF7L1a0vyvpQ9NM99FMlupChK/ pGheBDxLJbFTg== Message-ID: <64b10ef4-428c-47dc-a97c-59ba178a9044@kernel.org> Date: Tue, 22 Sep 2026 16:45:52 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RESEND v7 02/29] arm64: mm: add PMD swap-exclusive helpers To: Usama Arif , Andrew Morton , chrisl@kernel.org, kasong@tencent.com, ljs@kernel.org, ziy@nvidia.com, linux-mm@kvack.org Cc: ying.huang@linux.alibaba.com, Baoquan He , willy@infradead.org, youngjun.park@lge.com, hannes@cmpxchg.org, riel@surriel.com, shakeel.butt@linux.dev, alex@ghiti.fr, kas@kernel.org, baohua@kernel.org, dev.jain@arm.com, baolin.wang@linux.alibaba.com, Nico Pache , "Liam R. Howlett" , ryan.roberts@arm.com, Vlastimil Babka , lance.yang@linux.dev, linux-kernel@vger.kernel.org, nphamcs@gmail.com, shikemeng@huaweicloud.com, yosry@kernel.org, qi.zheng@linux.dev, luizcap@redhat.com, kernel-team@meta.com, Catalin Marinas , Will Deacon References: <20260914122950.3283997-1-usama.arif@linux.dev> <20260914122950.3283997-3-usama.arif@linux.dev> <35e42ccc-df8f-4703-b10d-f7c96b263e98@kernel.org> <93e71e27-86d7-4853-bbd2-756ac137a925@linux.dev> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <93e71e27-86d7-4853-bbd2-756ac137a925@linux.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 1036340016 X-Stat-Signature: byhxrt4qoa1ymec66emrmg7endzu4dcs X-Rspam-User: X-HE-Tag: 1790088366-976342 X-HE-Meta: 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 aM/fOPxR p+GQFK5dXu4eKRU16IHNX6e50M0XlbemVQFR/P2M+/5HV8a6Aur29AUKTSTQKvPbn9thz54bUTqz8MLvV1ybf+cad0MqA5zYKjs7sWvyi5IGOM6FtQiveqj7nUIHR83mqpcpIHe6SY+OrCsnj40puWQIG8AD/iWNDrfmqKGuuGzYQoVqCLvX7Ej7NZmyxwS5gNF9Si990L+LTvBLmj3Xj66/lWNZeONsjXy2WkDm11tR6HNmWBDRR4emgGm5leWFGvDMnSGpC1QmcxuWQKgbJ+47RqX7KbuRj6tqWXbZaiqWly5XpUdokD5Kbmk2SrLTeKkppST8khOr+Wf6psEAoHqRIZQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 9/22/26 14:34, Usama Arif wrote: > > > On 18/09/2026 22:11, David Hildenbrand (Arm) wrote: >> On 9/14/26 14:27, Usama Arif wrote: >>> A later patch keeps a PMD-mapped anonymous THP mapped by a PMD across the >>> swap round-trip, so PG_anon_exclusive now has to survive in a swap PMD and >>> not just in a swap PTE. >>> >>> arm64 encodes a swap PMD exactly like a swap PTE, so the new helpers wrap >>> the PTE ones and reuse PTE_SWP_EXCLUSIVE. >>> >>> Cc: Catalin Marinas >>> Cc: Will Deacon >>> Signed-off-by: Usama Arif >>> --- >>> arch/arm64/include/asm/pgtable.h | 6 ++++++ >>> 1 file changed, 6 insertions(+) >>> >>> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h >>> index e89ec5f4787b4..d3f53a601aed3 100644 >>> --- a/arch/arm64/include/asm/pgtable.h >>> +++ b/arch/arm64/include/asm/pgtable.h >>> @@ -599,6 +599,12 @@ static inline int pmd_protnone(pmd_t pmd) >>> #define pmd_swp_clear_uffd(pmd) \ >>> pte_pmd(pte_swp_clear_uffd(pmd_pte(pmd))) >>> #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */ >>> +#ifdef CONFIG_ARCH_HAS_PMD_SOFTLEAVES >>> +#define pmd_swp_exclusive(pmd) pte_swp_exclusive(pmd_pte(pmd)) >>> +#define pmd_swp_mkexclusive(pmd) pte_pmd(pte_swp_mkexclusive(pmd_pte(pmd))) >>> +#define pmd_swp_clear_exclusive(pmd) \ >>> + pte_pmd(pte_swp_clear_exclusive(pmd_pte(pmd))) >>> +#endif >> >> Why do we #ifdef that here, but not the uffd-wp swp PMD helper? >> > > uffd-wp is gated on CONFIG_HAVE_ARCH_USERFAULTFD_WP. > > If I removed the CONFIG_ARCH_HAS_PMD_SOFTLEAVES guards above, when THP=n, arm64 > will use the generic macro which is wrong. > > I tried building uffd-wp swp with just ARCH_HAS_PMD_SOFTLEAVES guard and I got > the build error > > mm/page_table_check.c:232:20: error: implicit declaration of > function 'pmd_swp_uffd' > > we will probably need a separate patch like: > > #ifdef CONFIG_ARCH_HAS_PMD_SOFTLEAVES > static inline bool pmd_softleaf_uffd(pmd_t pmd) > { > return pmd_swp_uffd(pmd); > } > #else > static inline bool pmd_softleaf_uffd(pmd_t pmd) > { > return false; > } > #endif > > > to avoid the above build error. Just to explain where I am coming from: for all these patches I took a look how the other pmd_swp_* functions where handled (and separated from the pte_swp_* variants). Nothing earth shattering, was mostly looking for keeping things consistent within these architecture codes. -- Cheers, David